I replaced the front brakes on 1990 celica. Since then the front brakes heat up and lock up and won't release.I replaced the front brakes on 1990 celica. Since then the front brakes heat up and lock up and won't release.

2001 sienna with same issue, but started happening before, and continues to happen, after replacing calipers, pads, rotors, and bled lines. Front brakes grab slightly, just enough to be felt when you let up on the gas, plus, rotors are always extremely hot, turned to dark blue due to heat. Interesting note, opened bleed valve on caliper and there was no fluid discharge, I would have expected to see some discharge had there been pressure in the line.

DT

2001 sienna with same issue, but started happening before, and continues to happen, after replacing calipers, pads, rotors, and bled lines. Front brakes grab slightly, just enough to be felt when you let up on the gas, plus, rotors are always extremely hot, turned to dark blue due to heat. Interesting note, opened bleed valve on caliper and there was no fluid discharge, I would have expected to see some discharge had there been pressure in the line.

It could be your master cylinder is pulling a vacuum on the lines. May be an indication of your mc failing or trapped or pocketed air in the lines. Not normal air in the lines, but, air that is trying to get out and as it does it pulls a vacuum. One other thing to look for is your brake calipers staying engaged to a certain degree, this could indicate failing calipers seal, fault brake line or wheel cylinder failure. Check out these things

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Related Questions:

ABS systems are designed to engage when braking suddenly causing tire skid/spin...the system is designed to pump the brake pedal and the driver should hold the brake pedal down firmly...DO NOT PUMP...the ABS does this for you.

Is the car equipped with the Automatic Transmission?
If so, read on.
Otherwise skip to the end and answer some questions.

POSSIBLE SCENARIO:
I have observed a condition where my car surges slightly when the torque-converter clutch (TCC) cycles between lock and unlock when driving on an uphill grade.
First some basics and history that will explain why the TCC is used.

Engine, Torque Converter, TCC, and Transmission relationship--
The TCC allows for a solid connection between the engine and transmission which allows the input to the transmission to rotate at the same speed as the engine.
Without a TCC, there is slippage between the engine and automatic transmission. The slippage is greatest at low engine RPM. That is what allows the engine to run with the automatic transmission in gear, like when you first shift into gear or stop at a stop sign. When the throttle pedal is depressed, the engine RPM begins to increase and the torque converter begins to slip less and less the more the engine RPM increases. The car moves. But even at cruising speeds the torque converter slips slightly. Engine RPM is greater than transmission input RPM, which is realized as slight decrease in fuel efficiency.
When acceleration is complete and a constant speed is being maintained, the engine power output is reduced to the point where the TCC can engage and eliminate any slippage between the engine and transmission. If the car has a tachometer the engagement of the TCC can be verified when a slight reduction in engine RPM observed without a corresponding change in vehicle speed.
One method used to test the operation of the TCC is as follows:
Find a flat section of road where it is safe to perform the test.
Reach a steady speed and keep the gas pedal depressed with one foot. While observing the tachometer (or listening for an increase in engine RPM), with the other foot depress the brake pedal enough to activate the break light switch but not enough to engage the brakes. When the brake light switch activates, the TCC receives a signal to disengage. With the gas pedal being held steady, release the brake pedal and the engine RPM should decrease when the TCC engages.
Old cars with Automatic Transmissions did not use a TCC. I believe the TCC was put in use in an attempt to increase fuel economy.

MY EXPERIENCE WITH SIMILAR SYMPTOMS
The condition that causes that issue on my car is this:
- A slight uphill grade increases the load on the engine.
The car tends to gradually slow and it is necessary to depress the gas pedal to maintain speed.
- Depressing the throttle pedal (manually, or automatically with cruise control engaged) signals the torque converter clutch to unlock when the load increases slightly. (A more drastic load increase would signal the Transmission to downshift to a lower gear.) The corresponding increase in engine RPM and output is enough to compensate for the reduction in speed. When the vehicle speed, engine RPM, and throttle position stabilize to the point that the TCC will engage and the engine RPM will reduce in correspondence with TCC engagement. Now, if the road conditions have not changed, power output is not enough to maintain vehicle speed. With the increased load caused by full engagement between engine and transmission, and the cycle (surging) repeats itself until the road conditions change.

Does that help?
If not:

QUESTIONS
Please define the symptoms.
What are the road conditions when the surge occurs? (A slight uphill grade?)
What is the frequency of the surge?
Does the engine power output have a noticeable surge?
Is there a speed change related to the surge?
Does the tachometer move up and down with little or no change in vehicle speed?
Are all instrument indication in the normal range?
What else has changed?

the cable runs along the underneath rail of the car on the left side. It is an obvious cable, like a wire type, kinda thicky. inspect that, and smooth any kinks out, possibly tighten it or perhaps a clip came out and its stretched on something foriengn. just smooth cable, do not stress because the parking break cable will re-release itself and you may want to disconnect the positive battery for a 30 second count and reconnect and the light on dash should go away permanently unkless it sticks down the road. you do not need to pull the handle so tight it experiences these situations. just gently pull up, click click type thing, make sure its engaged and you should depress brake pedal and raise handle when you go to release this parking brake, and make sure your key is in ignition, car running and then depress brake pedal with foot, as you gently pull up, depress clicker button and proceed slowly down which should dis-engage this parking brake and allow free vehicle movement to drive. good luck

u gut a master cylinder or booster issue--chec proper fluid level and condition--u cant see a leak in brakebooster where master attaches--u may have air inlines--bleed them if--a pro shud be considered

a lot of times the sensors on each wheel become covered with brake dust if you remove the wheels and clean the sensor with brake cleaner this will solve the problem but keep in mind it may happen again when the brake dust gets on the sensor again

The parking brake actuator (the mechanism you press with your foot) works like a ratchet wrench. The pedal has a cresent shaped plate with teeth on it. It pivots on a mounting plate. There is a pawl with a small spring also on the backing plate. This pawl engages the teeth on the pedal assembly to hold the brake engaged (against the large return spring). Stick your head under the dash and look carefully at the parking brake actuator mechanism. See why the pawl is not engaging the teeth on the pedal assembly. Most likely causes are that the release mechanism is jammed "on" or that the light spring which attaches to the pawl is missing (usually from being kicked by some one with large feet) View this mechanism on another GM vehicle with the same style parking brake if you suspect that parts are missing.Charlie

I would check the easy things first. That is the brake switch and the clutch switch (manual trans). Drive down the road and pull the brake pedal up with your foot and then try to set the cruise (same with the clutch pedal). Also the cruise requires that the brake light bulbs be in working order (and that there are no LED brake lights). Check fuse numbers 53 54 and 59.
The high beam problem might be related to the cruise issue, but I can't think of a reason why.